This project examines the function of various oral tissues during physiologic aging and in individuals with alterations of normal oral function due to disease or therapeutic procedures. Major efforts have been directed at the evaluation of patients complaining of xerostomia (oral dryness) utilizing the inpatient and outpatient services of the Dry Mouth Evaluation Clinic. Specific diagnostic approaches have been developed to aid in establishing the etiology of salivary gland dysfunction and defining criteria necessary for management decisions. A treatment protocol for selected patients with demonstrable functional gland mass yet inadequate basal salivary performance has been initiated, employing a regimen of oral administration of the parasympathomimetic drug, pilocarpine. In addition, detailed studies of salivary-associated oral complaints (eg taste and oro-pharyngeal swallowing disorders) have commenced. Such studies include evalution of oral sensorimotor performance across the adult life-span in order to better understand dysfunctional states. Studies on therapy-associated perturbations of oral function have concentrated on the effects of combined chemotherapy for neoplasia on salivary glands and oral soft tissues.